Patent GB-385831-A (GB)
Title: Improvement in regulating systems
IPC: F22D5/10
Filed: 1932-05-05
Abstract: 385,831. [Automatic regulators. BAILEY METER CO., 1050, Ivanhoe Road, Cleveland, Ohio, U.S.A.-(Assignees of Johnson, C. ; 2026, East 107th Street, Cleveland, Ohio, U.S.A.) May 5, 1932, No. 12975. Convention date, May 8, 1931. [Classes 69 (ii) and 135.] An automatic regulator for regulating the relationship between two values in such a way as to maintain a third value constant has a movable control element under the joint control of the two values acting in the sense to maintain the relationship between them normal and also under the control of the third value acting in the sense to maintain the third value normal. The Figures show the invention applied to the control of the feedwater supply to a steam generator. The feed valve is actuated by hydraulic pressure produced by a displacer actuated by fluid pressure under the control of a relay valve itself actuated by fluid pressure under the control of an auxiliary control valve operated by means responsive to the flow in the steam and water pipes and to the water level in the boiler. The control valve spindle 14 is coupled by a linkage 13 to the indicating elements 5, 10, 12 of flow meters 4, 8 and a water level indicator 11. The meters 4, 8 have differential pressure liquid sealed balls connected across apertured plates in the water and steam pipes respectively and the device. It comprises a U-tube connected to the boiler above and below the water level and housing in one limb an operating float. The control valve comprises a pair of cylindrical members 38 each having four tapered recesses formed by removing tapered segments and works in a ported sleeve 33 continuously rotated by a motor 18 acting through worm gearing 32 so that the control ports are only in the operative position twice during each revolution whereby the regulation is made intermittent. The sleeve 33 is splined to the spindle 34 of a rotary pump 35 mounted in a double piston 31 and discharging liquid drawn from a reservoir 43 into a passage 37. The passage 37 is constantly connected to the space between the valve members 38 and the space above a relay. valve member 39 coupled to the double piston. In the event of the control valve moving upwards oil is fed to the space above the upper piston through a passage 40 and exhausted from the space below the lower piston through passages 41, 42 leading to the reservoir. In the event of the control valve moving downwards oil is fed through the passage 41 to the space below the lower piston, and exhausted from the upper space through passage' 40, flooding the worm gear and returning to the reservoir through passage 44. As the double piston moves downward it moves the valve 39 to uncover a port in a sleeve 45 to admit oil to the interior of a bellows device 47. As the bellows expands it moves the sleeve to close the port. In the reverse direction the valve 39 operates to permit the return of oil from the bellows to the reservoir through a passage 49. The space between the bellows 47 and the casing 50 is filled with oil and connected by a pipe 16 to a bellows coupled to the spindle of the double beat feed valve. As the bellows is expanded oil is transferred to the bellows on the feed valve to open it against the action of a spring. In a modification, the loading spring is arranged beneath the bellows 47 and a separate source of fluid pressure supplies the valve 39. In a further modification the bellows 47 acts directly on the spindle of the feed valve. For hand operation a hand-wheel 20 is operated to turn a bell-crank lever 56 having a bifurcated arm 58 engaging projections on the double piston. The initial engagement of the arm 58 opens relief valves to vent the oil from the spaces above and below the pistons, and further movement brings the lower piston into engagement with the end of the sleeve 45 to expand the bellows positively. A pressure gauge 21 is arranged on the pipe 16 to indicate the pressure in the control conduit and hence the position of the feed valve. To maintain the feed valve in its last adjusted position in the event of the electric supply or the supply of pressure fluid failing a valve normally held open by a solenoid 23 in the motor circuit and another valve held open by the pressure in the conduit 37 acting on a bellows 67 are interposed in the conduit 16. In the event of the pressure in the pipe 16 falling below a predetermined minimum the circuit through a signal lamp 22 is completed by a pressure actuated switch.